Apparatus for splitting glass cylinders.



H. F. HITNER. APPARATUS FOR SPLITTING GLASS CYLINDERS.

APPLIUATION FILED MAR. 28, 1912.

WITNESSES; I INVENTOR. v By M ATTORNEY.

i Splitting UNITED STATES PATENT crimes.

HARRY F. HITNER, OF MOUNT VERNON, OHIO. ASSIGNOR TO THE PITTSBURGH PLATE e s- S OMPANY, or IT SBUR RENN VANIA .A .QQB OM' I R N SYLVANIA.

To dzzwlimtma bmm: Be it known that I, HARRY HITNRR, a' citizen of the United States,iresiding at Mount Ve'rnomin the county ofvKnox and -State of-Ohio, have. invented certa n new' and useful Improvements in Apparatus for.

Glass Cy1inders, .of: which the following'is aspecification. I.

I The invention relates to an apparatus for.

1o splitting lass cylinders-and it has forzits primary-o ject the-provisionof an improved;

electrically heated member: 3 for spIitting J glass cylinders which is simple in construction and may be conveirientlyandeconomi cally 'operateda This, vtogether withlsuchn other objects as may hereinafter appear or maygbe incidental to my invention, I at'-.

ta-in by means of a construction whichs'lhave illustrated in preferred-form in the accom diagrammatic illustration of a section-of a; glass cylinder; which is to *be split, showing; the operation of my improved electrically heated splitting member. Figure 2 is a side elevation of the splitting "member; Figure 3 is a cross section through the splitting member drawn on an enlarged scale-; and Figure 4 is a plan view of a detail of-my: invention likewise drawn on a large scale to more closely illustrate the-parts.

Heretofore in splitting glass cylinders, it has been customary to ay the sections of. cylinders on a table or other suitable support having a flat surface and then to recip rocate an iron splitting member which is heated to red hot condition back and forth along the inner surface of the cylinder adjacent the table. This method of splitting cylinders is objectionable because of the difficulty of heating the iron to the proper degree of heat; and because the iron loses its heat as successive cylinders are split. The heat of the iron is thus irregular and the iron is frequently either too hot or too cold, which results in breakage of the glass. The time lost in carrying back and forth the heated iron and also the expense involved for fuel for heating purposes and the rapid deterioration of the iron incident to the successive heatings increases the cost of production considerably. My invention contemplates the provision of a splitting member which will have a uniform degree of heat at all times, which will not be subject to fap'plica tiomflled narcnaaiaiaseriai xaesasae 1 I; frapid' deterioration and which will at ocoa .nomical in.- operation; In carrying out-my:

panying drawings 'wherein; Figure 51 isa v v i i handle 15 is fastened to'theblockY by meansi'lfi of the. screivs lfi and is adapted to recei=ve-:-..-

the wiresfl'l and 18 whichmay be connected a l invention, .I-employ an electrically heated. splitting ..member comprising a supporting: stripor block 7 preferably composediof-sas-- bestos wood on a similarl 'nonfconducting fia wsubstancathe lower edge of which is vroundw ed to conform to the shape of the-strip 18:, 1

which is preferably composedof a nonioxi- Y .dizing resistance alloy, such-for example as nickel chr0mium.: ;The resistancestrip 8 isprovided at each end with. upturned portions :9; and l0 and is supported on the-block 7 by i means of the stud '11 which-secures thehupl iturned portion 9' to the rear end of tlieblock and by'the spring/12 whic'h'is riveted to thelupturned portion 10: and isl s'ecure d to the a 'plate 13. by .means of the. screws 14', said "screvvs serving to. secure the spring'and platey to the: front end oftheblock 7z'- AL*hollow constitutes Y one terminal,- and the' wire =17 leads to the spring 12,;which constitutes :the other terminal of the strip 8. The wire 17 normally lies in thegroo ve QO'form'edinthe"- upper edge of the block 7. The operation of the device is as follows; assuming that the plug 19 has been inserted in a suitable socket. I

The current passing through the wires 17 and 18 and resistance strip 12 heats the resistance strip and when sufficient heat is generated, the implement is placed within a section of a cylinder 21 as indicated in Fig. 1, and is reciprocated longitudinally on the inner surface of the cylinder adjacent the supporting table or platform, as diagrammatically indicated at 22. The heat splits the cylinder lengthwise, after which the cylinder is turned through 180 and the operation is repeated, the cylinder being thus divided into two parts.

The resistance strip 8 is rounded in cross section and is of substantially the same width as the block 7, this form having been found most suitable to secure sufficient rigidity to prevent warping or other distortion of the heating strip. This is of importance as the strip 8 should be in substantial contact throughout its leng th with the to secure the most effective operation. As the co-eflicient of expansion and retraction of the resistance strip is greater than that of the supporting block g7,.I have :found itdesirable to fasten the resistance strip rigidly to but one end of the block 7 the other end being held yieldingly by the spring 12,; which is, however, of a sti fl'ness suflicient to prope'rlysuppo'rtthe strip on the block 7 It will be apparent 'fromjtheforeg'oing that the heat of the resistance strip will be uniform and continuous and that the "device is not only efl'ective but also economical ino eration.

The supportingblock 7 is prefera 1y composed of asbestos wood or similar substance which is a non-conductorof electricity and heat and is advantageous in that the/heat of the resistance strip is not absorbed and simplicity.' 0f insulation is obtained. The parts of the device are inexpensive and are easily assembled and repaired. It is further to be observed that the length of the heating memher is' less than that of the section of the cylinder being split,'in order that a small portion of the glass at each end of the cylmder will not bebrought upto heat until the central portion has been heated. This has been found to prevent breakage which occurs if the end portions ofjithe cylinder are heated sooner than the central portion, and in many cases if the end portions and central portions aresimultaneously heated.

Having thus described my invention'and illustrated its use, what I claim as new and desire to, secure by Letters Patent is the following:

1. A glass splitting device comprising a relatively rigid bar having one edge straight,

ar'elativelythin band of metal extending along and supported flatwise by the said edge, and means for sending a current of electricity through the strip of metal to heatit. I

2. A glasssplitting device comprising a relatively rigid bar of non-conducting material having one edge straight, a strip of metalof concave convex crosssection ex tending ,alongand supported by the said' edge with the'eoncave surface inward, and means for sending a current of electricity through the strip of metal to heat it.

[signed my name-in the presence of the two subscribed witnesses.

( HARRY F. HITNER.

' Witnesses:

A H. V. I-Lmcocn,

QBARMER M. ALLEN.

Copies 6! this patent may be obtained for five cents each, by addressing the Commissioner or lateatl.

' Washington, D. 0, 

